How to check for an array entry?

Question

JavaScript

Hello, I'm trying to experiment with backbone js.
I wanted to make a simple collection filter

var mClub = new Cafe([
    {id: 1, name: "name 1", kitchens: [1,2], show: 1},
    {id: 2, name: "name 2", kitchens: [1,3], show: 1},
    {id: 3, name: "name 3", kitchens: [2], show: 1},
    {id: 4, name: "name 4", kitchens: [1], show: 1},
    {id: 5, name: "name 5", kitchens: [3], show: 1},
]);

var filters = new Filter([
    {id: 1, kitchens: new Array()}
]);

the “kitchens” filter is filled in as the appropriate parameters are selected.
Now the task is to sort the mClub collection if at least one parameter from the filters is found in kitchens, then leave show 1 if not, then 0 I
thought the indexOf approach should be suitable for this - as a result, this is the code

var Cafe = Backbone.Collection.extend({
    model: CafeModel,

    check : function(filter) {
        var show = true;
        var a = filter.get('kitchens');
        this.filter(function(cafe) {
            var b = cafe.get('kitchens');

            // Попытка с indexOf - не работает
            // если задать а и b ручками - то работает
            // var a = [1,3]; var b = [3,2]
            for (var i = 0; i < b.length; i++){
                if(_.indexOf(a, b[i])){
                    //alert('есть вхождение')
                }
            }
           //через фильтр - работает
            b.filter(function(c){
                for (var i = 0; i < a.length; i++){
                    if( a[i] == c){
                        //alert('есть вхождение')
                    }
                }
            });
        });
    }
});

Maybe I'm doing something wrong and maybe someone will tell you a better way, later the filter will be supplemented with other parameters.

Answer 1

in operator

Answer 2

I would do like this:

var filter = new Filter();
filter.add([
    {id: 1, kitchens: new Array()},
    {id: 2, kitchens: [2]},
    {id: 3, kitchens: [2, 3]},
    {id: 4, kitchens: []}
])

Filter = Backbone.Collection.extend({
    initialize : function() {
        this.on('add', this.check);
    },
    check : function(model) {
        model.set('show', model.get('kitchens').length ? 1 : 0);
    }
});

You can also use the validate method for the model, but in my opinion it has a slightly different purpose

Answer 3

Another interesting moment is how to make a chain of filters, now I have driven all the checks into one check function

Answer 4

All this can be underscored (as backbone prequels), either through a filter or an include. For chain .chain().… .value()

Answer 5

http://stackoverflow.com/questions/11762105/filter-backbone-collection-by-attribute-value interesting method